Electric coffee maker



May 17, 1938. c. D. KEAToN 2,117,729

ELECTRIC COFFEE MAKER Filed Jan. 29, 1937 ATTORNEYS Patented May 17, 1938 UNITED STATES ELECTRIC COFFEE MAKER Clyde D. Keaton, Long Island City, N. Y., as-

signor to Stanley S. Tumbrdge, New York,

Application January 29, 1937, Serial No. 122,945

18 Claims.

The object of my invention is to provide an electric coiee maker of he vacuum type in which automatic means under the control of the contents of the coieepot is employed to cut oil the heat when the co' ,ee reaches a predetermined point in its making.

A further object of my invention is to provide automatic means for hastening the cooling of the electric heating ezment when the current is cut off therefrom.

My invention comprises, generally, an electric coffee maker of the above type in which the electric heater is provided with a heating element, the circuit being completed therethrough by the manual setting of a switch in the circuit.

My invention further comprises an electric coffee maker in which the circuit through the heating element is cut off when the water in the lower chamber of the coll'eepot is forced upwardly into the upper chamber thereof through a illter of well known or approved form.

My invention also comprises an automatic ventilator for air cooling the heating element when the circuit therethrough has been broken, said ventilator being closed when the current is passing through the heating element.

My invention still further comprises an electric coilee maker in which a. hand lever is used to operate a switch in the circuit to complete the circuit through the heating element, said hand lever being under the control of the contents of the coifeepot for throwing the lever to open the switch and thereby open the circuit through said heating element.

Practical embodiments of my invention are represented in the accompanying drawing, in which- Fig. 1 represents a vertical central section through one embodiment of my invention in which a thermostat controlled by the variations of heat in the lower chamber of the coieepot is provided for opening and closing the circuit through the heating element;

Fig, 2 represents a detail side view of the air controlling shutters for the heating chamber;

Fig. 3 represents a detail vertical central section through a second embodiment of my invention in which two spaced terminals are located in the lower chamber of the coileepot, said terminals being electrically connected land disconnected as the water rises and falls in said lower chamber; and

Fig. 4 represents a similar section through a third embodiment of my invention in which the rise and fall of steam pressure in the lower chaming communication betweenV the lower and upper chambers of said vessels.

The upper vessel 2 may be provided with a removable cover 4. The lower vessel may be proided with a handle 5 and a pouring spout S, within which pouring spout there is seated a weighted valve 1, in the present instance of the ball type for preventing the escape of steam from the lower chamber through the said spout.

The electric heater casing which is formed integral with the lower vessel l of the coileep'ot is denoted as a whole by 8. This casing 8 is provided with a heating chamber 9 in which the heating element l0 is located. Shutters Il, pivoted at l2, serve to open and close the open bottom of the heating chamber 9. These shutters are held closed against their tendency to open by gravity by providing the shutters at one side of their pivots I2 with upturned lips I3 engaged by a horizontal plate I4 connected by an upright rod l5 to a horizontally disposed hand lever I6 pivoted at l1 to a bracket I8 uprising from the bottom of the heater casing 8. A spring I9 tends to lift the hand lever I6 to the limit of its upward movement against a stop 20. This hand lever is releasably held at the limit of its, downward movement by an electromagnet 2l and its trip lever 22 pivoted at 23 to the bottom of the heater casing 8. This trip lever 22 is provided with a shoulder 24 which engages a projection 25 on the hand lever I6 when the trip lever 22 is swung to the limit of its forward movement by the energization of the electromagnet 2l. A spring 26 serves to swing the lever 22 outwardly when the electromagnet 2l is deenergized, to' release the projection 25 from the shoulder`24 of the said trip lever 22.

A switch 21, in the present instance a mercury switch is mounted on the hand lever I6 in position to close the circuit through the switch when the hand lever is in its depressed position and to open the circuit through the switch when the hand lever is in its raised position.

'Ihe main line wire 2B leads'into the heater to the heating element lll. A wire 29 leads from the heating element I0 upwardly in the handle 5 to a thermostat 30 which is located close to the outer wall of the lower vessel l of the coffeepot. A wire 3l also located in the handle 5 leads from the thermostat Il to the electromagnet 2|. A wire 32 leads from the electromagnet 2I to the switch 21 and the other main line wire 33 leads from the switch 21 outwardly through the heater casing.

Inthe form shown in Fig. 3, the wires 26 and 3| are provided with terminals 34 and 36 located within the lower chamber of the cofleepot, the electric circuit at this point being made and broken by the water as it rises and falls within the said lower chamber to points above and below the terminals Il, 6l.

In the form shown in Fig. 4, the trip lever 22 for the hand lever I6 is pressure controlled by a pump 36, the interior of which pump on one side of the piston 31 which is carried by the trip lever 22 is open to pressure within the lower chamber of the coffeepot through the passage 36 which leads from the pump to the upper end of the said lower chamber. Pressure upon the opposite side of the piston 31 is exerted by means of a spring 39, which spring also tends to hold the trip lever 22 in its locking engagement with the hand lever I6. The piston rod 40 carries a contact plate 4I arranged to open and close the circuit through the wire 42 leading from the heating unit I0, and the wire I3 leading to the switch 21.

In the form shown in Fig. l, the operation is as follows:

The upper and lower chambers of the coffeepot are supplied with the desired amounts of ground coffee and water respectively. 'I'he hand lever I6 may then be depressed, thereby closing the shutters II and tilting the mercury switch 21 to close the circuit at this point. The depression of the hand lever I6 will cause the energization of theelectromagnet 2I and cause the trip lever 22 to be moved inwardly to lock the hand lever I6 in its depressed position. With the parts in these positions the circuit is passing through the heating element andthe water in the coileepot is subjected to the heat therefrom. After the water has been boiled and most of it has passed up into the upper chamber through the lllter 3 the heat in the lower chamber rises lto a point which causes the thermostat 30 to open and thereby break the circuit through the heating element and also through the electromagnet 2|. This will cause the trip lever 2.2 to release the hand lever I6 and permit the hand lever to swing upwardly to open the shutters and to tilt the mercury switch 21 to also open the circuit at this point;

In the form shown in Fig. 3, the operation is quite similar with the exception that the water in the lower chamber closes or opens the' circuit across the terminals 34, as the water rises or falls to levels above and below the terminals.

In the form shown in Fig. 4, the pump 36 which operates the trip lever 22 is controlled by the rise and fall of the fluid pressure within the lower chamber of the coileepot. Otherwise the operation is quite similar to the operation of the forms shown in Figs. l and 3.

It is evident that various changes may be resorted to in the construction, form and arrangement of the several parts without departing from the spirit and scope of my invention, and hence I donot intend to be limited to the particular embodiments herein shown and described, but- What I claim'is: A

1. In an electric coffee maker, a casing having a heating chamber, a heating element therein, a ventilator for the heating chamber, a colleepot, manually operated means for closing the ventilator and also closing the` circuit through the heating element, and automatic means controlled by the contents of the collec-pot for opening the circuit through the heating element and also for opening the ventilator yto cool the heating element.

2.'In an electric coffee maker, a casing having a heating chamber, a heating element therein, a ventilator for the heating chamber, a colleepot including a lower vessel formed integral with the heater casing, manually operated means for closing the ventilator and also closing the circuit through the heating element. and automatic means controlled by the contents of the coll'eepot for opening the circuit through the heating element and also for opening the ventilator to cool the heating element.

3. In an electric coffee maker, a casing having a heating chamber, a heating element therein, Ventilating shutters for the heating chamber, a coileepot, a hand lever for closing the shutters and also closing the circuit through the heating element, and automatic means controlled by the contents of the cofleepot for opening the circuit through the heating element and also for A opening the shutters.

4. In an electric coffee maker, a casing having a heating chamber, a heating element therein, Ventilating shutters for the heating chamber, a coileepot including a lower vessel formed integral with the heater casing, a hand lever for closing the shutters and also closing the circuit through the heating element, and automatic means controlled by the contents of the cofleepot for opening the circuit through the heating element and also for opening the shutters.

5. In an electric cofiee maker, a casing having a heating chamber, a heating element therein, a ventilator for the heating chamber, a cofleepot, manually operated means for closing the ventilator and also closing the circuit through the heating element, and automatic means controlled by the contents of the coifeepot for opening the circuit through the heating element and also for opening the ventilator to cool the heating element, saidautomatic means including a thermostat carried by the coileepot.

6. In an electric coffee maker, a casing having a heating chamber, a heating element therein. a ventilator for the heating chamber, a coil'eepot including a lower vessel formed integral with the heater casing, manually operated means for closing the ventilator and also closing the circuit through the heating element, and automatic means controlled by the contents of the coileepot for opening the circuit through the heating element and also for opening the ventilator to cool the heating element, said automatic means including a thermostat carried by the coffeepot.

7. In an electric coiiee maker, a casing having a heating chamber, a heating element therein, a ventilator for the heating chamber, a coffeepot, manually operated means for closing the ventilator and also closing the circuit through the heating element, and automatic means controlled by the contents of the coffeepot for opening the circuit through the heating element and also for opening the ventilator to cool the heating` element, said automatic means including spaced terminals in the coieepot.

8. In an electric coffee maker, a casing having a heating chamber, a heating element therein, a ventilator ifor the heating chamber, a coifeepot including a lower vessel formed integral with the heater casing, manually operated means for closing the ventilator and also closing the circuit through the heating element, and automatic means controlled by the contents of the coiieepot for opening the circuit through the heating element and also for opening the ventilator to cool the heating element, said automatic means including spaced terminals in the coieepot.

9. In an electric coffee maker, a casing having a heating chamber, a heating element therein, a ventilator for the heating chamber, a coiieepot, manually operated means for closing the ventilator land also closing the circuit through the heating element', and automatic means controlled by the contents of the coieepot for opening the circuit through the heating element and alsoor opening the ventilator to cool the heating element, said automatic means including a pressure controlled pump.

lll. In an electric coffee maker, a casing ha a heating chamber, a heating element there ventilator for the heating chamber, a co including a lower vessel formed integral with heater casing, manually operated means for ing the ventilator and also closing the ci through the heating element, and antenati-c means controlled by the contents of the coifeepot i'or opening the circuit through the heating el ment and also for opening the ventilator to :ooi the heating element, said automatic means inn cluding a pressure controlled pump.

1l. In an electric coffee maker, a casing hav' ing a heating chamber, a heating element therein, Ventilating shutters for the heating chamber, a coife'epot, a hand lever for closing the shutters and also closing the circuit through the heating element, and automatic means controlled by the contents of the coiieepot for opening the circuit through the heating element and also for opening the shutters, said automatic means including a thermostat in the coffeepot, a switch car tied, by the hand lever, a trip lever and an electromagnet for operating it. 12. In an electric coil'ee maker, a casing having' a heating chamber, a heating element therein, Ventilating shutters for the heating chamber, a coifeepot including a lower vessel formed integral with the heater casing, a hand lever for closing the shutters and also closing the circuit through the heating element, and automatic means controlled by the contents of the cofl'eepot for openling the circuit through the heating element and also for opening the shutters, said automatic means including a thermostat in the coiieepot, a switch carried by the hand lever, a trip lever and an electromagnet for operating it.

13. In an electric coffee maker, a casing having a heating chamber, a heating element therein, Ventilating shutters for the heating chamber, a coii'eepot, a hand lever for closing the shutters and also closing the circuit through the heating element, and automatic means controlled by the contents of the coeepot for opening the circuit through the heating element and also for opening the shutters. said automatic means including a pair ot spaced terminals in the coileepot, a

switch carried by the hand lever, a trip lever and an electromagnet foroperating it.

14. In an electric coiee maker, a casing having a heating chamber, a heating element therein, Ventilating shutters for the heating chamber, a coifeepot including a lower Vessel formed integral with the heater casing, a hand lever for closing the shutters and also closing the circuit through 'the heating element, and automatic means controllen by the contents of the coffeepot for opening the circuit through the heating element and also for opening the shutters, said automatic means including a pair of spaced terminals in the c "ieepot, a switch carried by the hand lever, a trip lever and an electromagnet for operating it.

an electric coee maker, a casing having a heating chamber, a .heating element therein,

- e heating chamber, a

n lever lor closing the shutters lso closing the circuit through the heating t, and automatic means controlled by the ts of coffeepot for opening the circuit h the heating element and also for opening the shutters, said automatic means including a switch on the hand lever, a trip lever and a '.uici 1 ressure controlled pump for operating it.

1S. In an electric coffee maker, a casing having a heating chamber, heating element therein, Ventilating shutters for the heating chamber, a cofeepot including a lower vessel formed integral with the heater casing, a .hand lever for closing the shutters and also closing the circuit through the heating element, and automatic means controiled oy the contents of the coiieepot for opening the circuit through the heating element and also for opening the shutters, said automatic means including a switch on the hand lever, a trip lever andl a fluid pressure controlled pump for operating it.

i7. In an electric cciee maker, a casing having a heating chamber, a heating element therein, a ventilator for the heating chamber, a coifeepct including a lower vessel having a handle and a valved pouring spout, manually operated means for closing the circuit through the heating element and also closing the ventilator, and automatic means controlled by the contents of the cofieepot for opening the circuit through the heating element and also for opening the Ventilator.

18. In an electric coiee maker, a casing having a heating chamber, a heating element therein, a. ventilator for the heating chamber, a cofieepot including a lower vessel having a handle and a valved pouring spout, said lower vessel being formed integral with the heater casing, manually operated means for closing the circuit through the heating element and also closing the ventilator, and automatic means controlled by the contents or the coieepot 4for opening the circuit through the heating element and also for opening the ventilator.

CLYDE D. KEATON. 

